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Troubleshooting Leaking Joints
 One
of the best available tools to aid in determining
the cause of leakage is a careful examination of the
gasket in use when leakage occurred.
Gasket Badly Corroded
Select
replacement material with improved corrosion
resistance
Gasket Extruded Excessively
Select
replacement material with better cold flow
properties, select replacement material with better
load carrying capacity - i.e., more dense.
Gasket Grossly Crushed
Select
replacement material with better load carrying
capacity, provide means to prevent crushing the
gasket by use of a stop ring or re-design of
flanges.
Gasket mechanically damaged due to overhang of
raised face or flange bore.
Review
gasket dimensions to insure gaskets are proper size.
Make certain gaskets are properly centered in joint.
No apparent gasket compression achieved
Select
softer gasket material. Select thicker gasket
material. Reduce gasket area to allow higher unit
seating load.
Gasket Substantially thinner O.D. than I.D.
Indicative
of excessive "flange rotation" or bending. Alter
gasket dimensions to move gasket reaction closer to
bolts to minimize bending movement. Provide
stiffness to flange by means of back-up rings.
Select soft gasket material to lower required
seating stresses. Reduce gasket area to lower
seating stresses.
Gasket unevenly compressed around circumference
Improper
bolting up procedures followed. Make certain proper
sequential bolt up procedures are followed.
Gasket thickness varies periodically around
circumference.
Indicative
of "flange bridging" between bolts or warped
flanges. Provide reinforcing rings for flanges to
better distribute bolt load. Select gasket material
with lower seating stress. Provide additional bolts
if possible to obtain better load distribution. If
flanges are warped, re-machined or use softer
material.>>The End
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